Montgomery County prosecutors dropped charges against an 18-year-old D.C. man identified as a suspect in the killing of an American University professor and plan to extradite him to the District to face charges there.

Deandrew Hamlin, 18, was facing charges related to the theft of a Jeep Cherokee that belonged to Sue Ann Marcum, 52, of Bethesda, who was killed in her home on Oct. 26.

Hamlin was caught driving the stolen vehicle in the District and was extradited to Montgomery County, which is investigating Ms. Marcum’s homicide. He will face charges in the District of unauthorized use of a vehicle.

Seth Zucker, a spokesman for Montgomery County State’s Attorney John McCarthy, said the case is an open and active police investigation.

“We’re deferring to the D.C. prosecution because it’s a more direct case for D.C. It’s the same charge. They both involve auto theft,” Mr. Zucker said.

But the development raises questions about the status of the murder investigation.

Mr. McCarthy argued personally in November that Hamlin be held without bond, calling him a “critical person” in the case and detailing how Hamlin gave investigators multiple accounts of how he came into possession of the vehicle. The prosecutor said in court that the keys to the Jeep were taken from inside Ms. Marcum’s house.

Montgomery County police treated the case as a homicide triggered by a burglary gone wrong and reported finding signs of a break-in and struggle in the lower level of the house.

Hamlin, a ward of the District’s Department of Youth Rehabilitation Services, will appear before a D.C. Superior Court judge on April 12.